HELP! VR screen was stretched in Editor Runtime

Development Platform & Builds XR Development
1

After engine version upgrade to 4.25.3,I create a new VR project,play with VR, then screen was stretched like this:
1.how to fix this?Need help

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1597110766(1).jpg1296×759 98.9 KB

2

I copied UE4Editor-Engine.dll from 4.25.1 To 4.25.3, replace the UE4Editor-Engine.dll, After then everything was back to normal.But I don’t know why…